Interfacing CNC shield v4 with laser engraver

Other Hardware Motors, Mechanics, Power and CNC
1

Hello everyone, I would very much appreciate any help on this,

I am trying to get a laser working correctly with Arduino CNC shield v4 (grbl 0.9). The 2 axes work well and can be controlled using grbl controller, the laser also works well and fires at full power when supplied with 12V.
Most other projects I've seen connect the PWM of the laser to Z-/+ however this does not work for me, I've tried:

  • powering the laser from external and connecting the laser PWM to Z.
  • powering the laser from the MOT_VOT_Sel pins from the shield and connecting the laser PWM to Z (and other pins).
    With the first, the laser switches on as soon as power is provided and with the second I get the fan on the laser working but I cannot control it with Laser GRBL even though the CNC connects well.
    The manufacturer of the laser says it has a built-in driver, but when I looked inside, yes there is a circuit board but I am not sure this is an actual laser driver, therefore do I need to get laser driver module like this one to get the laser to be controlled with the CNC shield?

Thank you for your help

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Your link to your laser describes built in driver, Ttl/pwm.
If you connect yellow wire to arduino vcc/gnd does it turn on/off?

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Hey kmin, thank you!! your message alone was enough to trigger the finding of the solution, in fact yes, when I connected the GND and PWM of the laser to the Mot_VOT_Sel of the arduino shield the laser started blinking at a low frequency, this means the driver is bluilt-in and actually working. Then I simulated an engraving using LaserGRBL, using an oscilloscope I read the signal and saw that PWM is coming from Z+, I connected GND and PWM of the laser to Z+ and corresponding GND on the board while leaving the +12 connected to Mot_VOT_Sel and the laser worked as it should, I can now control it and engrave.

Thanks again for taking the time to post a message!

4

Good luck with your project!

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